In a semiconductor manufacturing process, a plasma processing apparatus for performing a plasma processing for the purpose of, e.g., a thin film deposition, an etching or the like is widely used. The plasma processing apparatus may be configured as, e.g., a plasma CVD (Chemical Vapor Deposition) apparatus for performing thin film deposition, a plasma etching apparatus for performing an etching process, or the like.
The plasma processing apparatus includes a processing chamber for defining a plasma processing space, a gas supply system for introducing a processing gas required for plasma reaction into the processing chamber, and the like. Further, the plasma processing apparatus includes a lower electrode provided in the processing space and configured to mount thereon a target object to be processed, an upper electrode provided in the processing chamber to face the lower electrode, and the like.
In the plasma processing apparatus, it is known that an etching rate of a target substrate to be processed in the case of using a new upper electrode installed in the plasma processing apparatus is different from an etching rate of a target substrate to be processed in the case of using a used upper electrode. This is because a surface of the new upper electrode, which has not yet been exposed to a plasma, has a lower surface roughness compared to that of the used upper electrode. This makes a state of a plasma generated by using the new upper electrode different from a state of a plasma generated by using the used upper electrode.
In order to suppress the etching rate variation, there is used a technique for detaching an upper electrode from the plasma processing apparatus and roughening a surface of the upper electrode by performing surface treatment such as a wet etching, a sandblasting or the like (see, e.g., Japanese Patent Application Publication No. 2001-85405).
However, the conventional technique is disadvantageous in that the operation of detaching the upper electrode may deteriorates the operation efficiency of the plasma processing apparatus. Therefore, it is desired to roughen the surface of the upper electrode without the detaching operation.